Ten environmental advocacy groups in Massachusetts filed a federal lawsuit Friday against the US Environmental Protection Agency, seeking a court order to force the agency to implement a landmark plan to curb pollution in the state’s lakes, rivers, and streams.

After nearly a decade of negotiations among local, state, and federal authorities, the EPA announced this summer that it was shelving the plan, known as the MS4 stormwater permit, for at least another year.

The advocacy groups fear that the Trump administration will use the time to weaken or eliminate the plan, which would require municipalities to remove illegal sewer connections to storm drains, improve street sweeping, increase public education, and take other steps to cut the volume of stormwater entering sewer systems.

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“Stormwater is the state’s No. 1 pollution problem,” said Julia Blatt, executive director of the Massachusetts Rivers Alliance, one of the groups that filed the lawsuit. “The EPA pulled the rug out from under the state’s pollution control efforts by announcing this delay two days before the effective date.”

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EPA officials in Boston and Washington did not respond to requests for comment.

State officials had the option of pressing ahead, but they declined to do so.

The plan would require 260 Massachusetts municipalities to reduce stormwater runoff, a mandate that some cities and towns said could cost them millions of dollars a year and thousands of hours of their employees’ time.

In 2014, the EPA estimated that urban municipalities would be required to spend between $1.1 million and $2.5 million to comply with such regulations. Suburban and rural towns would pay less.

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At the end of June, EPA officials announced they were delaying the rules, saying they were acceding to requests from municipalities, such as Lowell and Franklin, that oppose the plan.

In addition to the Massachusetts Rivers Alliance, the plaintiffs include other groups that advocate for rivers and watersheds across the state.

“The stay of the MS4 permit was a gross overreach by an administration that has set out to systematically undermine protections to the environment,” said Patrick Herron, executive director of the Mystic River Watershed Association. “This permit was eight years in the making and long overdue. Further delay of the permit does not make any sense.”